Tailoring the magnetic properties of CoFeNi alloys with variations in copper contents

Abstract

CoFeNi alloys are some of the most studied soft magnetic materials because of their superior properties over FeNi alloys as write head core materials in hard disk drives. Pulsed electrodeposition was shown to be an interesting approach to vary the crystalline structure of the fcc-bcc mixed phase CoFeNi and CoFeNiCu films without changing the composition and the grain size by using a single bath. The permeability mu of CoFeNiCu films plated from bath composition exceeded 4.6x10(6). Coercivity H-c was 20-73 A/m. The high saturation magnetic flux B-s was 1.8 T. The soft magnetic CoFeNiCu film prepared satisfies all the requirements needed for the preparation of magnetic recording heads, as all magnetic properties were improved in this direction. (C) 2006 American Institute of Physics.